[Treatment of nausea and vomiting with 5HT3 receptor antagonists, steroids, antihistamines, anticholinergics, somatostatinantagonists, benzodiazepines and cannabinoids in palliative care patients : a systematic review].

BACKGROUND: Various recommendations exist for the treatment of nausea and vomiting in palliative care but only few studies and even less systematic reviews look into antiemetic therapy for patients receiving palliative care.
OBJECTIVES: This systematic review aims to analyze the current evidence for antiemetic treatment with 5HT3 receptor antagonists, steroids, antihistamines, anticholinergics, somatostatin analogs, benzodiazepines and cannabinoids in palliative care patients with far advanced cancer not receiving chemotherapy or radiotherapy, acquired immune deficiency syndrome (AIDS), chronic obstructive pulmonary disease (COPD), progressive heart failure, amyotrophic lateral sclerosis (ALS) or multiple sclerosis (MS). Results regarding evidence of treatment with prokinetic and neuroleptic agents will be published separately.
METHODS: The electronic databases PubMed and EmBase were systematically searched for studies (published 1966-2011) dealing with antiemetic therapy in palliative care and electronic retrieval was completed by manual searching. Studies with patients undergoing chemotherapy or radiotherapy, pediatric studies and studies published in languages other than English or German were excluded. Studies addressing therapy with 5HT3 receptor antagonists, steroids, antihistamines, anticholinergics, somatostatin analogs, benzodiazepines or cannabinoids were identified and selected for this systematic review.
RESULTS: In the general search 75 relevant studies were found. Of those 36 addressed 5HT3 receptor antagonists, steroids, antihistamines, anticholinergics, somatostatin analogs, benzodiazepines and cannabinoids, 13 considered 5HT3 receptor antagonists, 10 somatostatin antagonists, 9 steroids, 5 cannabinoids, 4 anticholinergics, 1 antihistamines and none benzodiazepines. Furthermore six systematic reviews exist. Evidence for any drug used as an antiemetic is low. Concerning 5HT3 receptor antagonists data are insufficient for recommendations on the treatment of patients with AIDS and MS due to the small size of included patient groups. For patients with cancer contradictory results were published: the larger studies showed a positive effect of 5HT3 receptor antagonists and better efficacy, as compared to metoclopramide, dexamethasone and neuroleptics. Heterogeneous results were found for steroids, with a positive trend for patients with cancer. Data are insufficient for antihistamines. Studies prove effectiveness of butylscopolammonium in the treatment of nausea and vomiting caused by malignant gastrointestinal obstruction, whereas octreotide is superior to butylscopolammonium. Regarding benzodiazepines for symptom control of nausea and vomiting in palliative care patients no studies were detected. Cannabinoids were found to relieve nausea and vomiting in patients with cancer and AIDS but with notable side effects. Furthermore, the studies compared cannabinoids to less recent antiemetic drugs but not, for example to 5HT3 receptor antagonists. Regarding symptom control of nausea and vomiting in patients with COPD, progressive heart failure and ALS no studies were undertaken in patients receiving palliative care.
CONCLUSIONS: In palliative care patients with nausea and vomiting 5HT3 receptor antagonists can be used if treatment with other antiemetics, such as metoclopramide and neuroleptics is not sufficient. There is a trend that steroids in combination with other antiemetics improve symptom relief. Cannabinoids rather have a status as a second line antiemetic. In cases of nausea and vomiting caused by malignant gastrointestinal obstruction octreotide showed the best and butylscopolammonium bromide the second best results. Concerning antihistamines and benzodiazepines insufficient data was found. Recommendations in the literature are mainly based on studies in patients with cancer. The overall strength of evidence is low. More well designed studies in palliative care patients are needed in order to provide evidence-based therapy. The English full text version of this article will be available in SpringerLink as of November 2012 (under "Supplemental").